Preparing the fabric before starting the eco printing process is commonly known as mordanting or pre-treatment.
The main purpose of this process is to ensure that the fabric is clean and ready to absorb natural pigments from plants without any barriers within the fibers.
For this reason, the fabric should be thoroughly washed using natural soap to remove dust, oils, wax, and other impurities.
In general, after washing, the fabric is soaked in a warm alum solution. Some artisans prefer to simmer the fabric in an alum solution instead.
The fabric may be soaked in the warm alum solution up to two times, with each soaking lasting at least one hour, depending on the type of fabric. Alum helps open the fabric fibers while also removing or settling fine particles through its natural coagulation properties.
High quality natural fabrics made from pure natural fibers, without polyester blends, usually require a shorter mordanting process.
To enhance the mordanting process, the following optional steps may also be applied:
- Before soaking in the alum solution, the fabric can be soaked in a tannin-rich solution made from tea, jolawe fruit, mango leaves, coconut husk, guava leaves, or other natural tannin sources.
- After the alum treatment, the fabric may be soaked once more in either a clear lime water solution (calcium hydroxide) or an iron sulfate (ferrous sulfate) solution.
Once these preparation steps are completed, the fabric is ready for the eco printing process.
